Self-Cooling Gradient Shell for Body Armor.

摘要

Current methods of reducing physiological strain on a soldier wearing armor vest need significant improvement. To this end, the major objective of this work was to conduct research on development of effective lightweight evaporative cooling system capable of delivering significant cooling effect without or with minimal power requirements and additional weight load. During the project we developed major methodology and equipment to measure cooling power and temperature effect of virtually any cooling system arrangements in laboratory conditions reliably. Resultantly, Surface Differential Scanning Calorimeter (SDSC) was created. In addition, we design and test a novel autonomous evaporative cooling system. As a result of the work several cooling arrangements utilizing an evaporative cooling mechanism were created. The driving force enabling significant evaporation is the temperature difference between parts of the arrangement created by cooling metal foil located on the outside of the vest. The best system demonstrated cooling power of about 100 W/m2 and surface cooling effect of 7-8 oC without using any external power source. The system is extremely lightweight, compact and self- sufficient. We also developed the procedure for preparation of hydrophobic membrane assembly and large hydrophobic-hydrophilic gradient fabric for directional water transport inside of the cooling system.